could take anything up to 4 days, again depending on how good your bank is.
The UK banking system is shit basically, all over the world money gets transfered within 24 hours, over here though, whilst your money is in 'transition' the banks earn interest off it, so they let it take as long as possible.
Just trot down with your details, and the person who your sending the money to details, and have a word.
They'll transfer it striaght away for you, but i'd be suprised if it appears in their account within the next 3 days after it's sent.